Hydraulic turbine



A. PFAU.

' HYDRAULIC TURBINE.

APPLICATION FILED APR.29. 1m.

1 ,309,809. Patented July 15, 1919.

THE COLUMBIA PLANDGRAPH 60-, WASHINGTON, D.. c.

UNITED STATES PATENT OFFICE.

ARNOLD PFAU, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO ALLIS-CI-IALMERSMANUFACTURING COMPANY, OF MILWAUKEE, WISCONSIN, A CORPORATION OFDELAWARE.

HYDRAULIC TURBINE.

Patented July 15, 1919.

Application filed April 29, 1918. Serial No. 233,583.

To all whom it may concern Be it known that LARNOLD PFAU, acitizen ofthe United States, residing at Milwaukee, in the county of Milwaukee andState of Wisconsin, have invented a certain new and useful Improvementin Hydraulic Turbines, of which the following is a specification.

This invention relates to improvements in the construction ofhydro-electric installations and is particularly applicable to hydraulicturbine installations of the direct connected, vertical shaft type.

An object of the invention is to provide a hydraulic installation whichis of simple and rigid construction, eflicient in operation, and inwhich the cost of installation is reduced to a minimum.

The present invention is particularly applicable to hydroelectricinstallations of the type in which a turbine runner is direct connectedto the lower extremity of a vertical main shaft, to the upper extremityof WlllCh a generator rotor is direct connected, and in which a pit ofsufficient vertical height is provided between the hydraulic andelectric machines to permit ready access to the turbine controllingmechanism and to the mam shaft bearing. In installations of this type itis also desirable in many cases to locate the generator at a sufiicientheight above the turbine to place it beyond danger of flooding by thehead waters, such location of the generator also being a factoraflecting the pit depth.

It has heretofore been customary in installations of the vertical shafttype wherein the generator is. of such overall diameter that it extendsconsiderably beyond the periphery of the turbine speed ring, to utilizea cast metal spiral inlet casing and to sup port the generator andassociated elements directly upon this casing. Such cast metal casingsare, however, both expensive to construct and to transport when made ofsufiicient strength to withstand the high internal and externalpressures to which they are subjected after installation.

In order to reduce the initial cost of construction andoftra'nsportation, as Well as thus forming the inlet casings it has beenfound that the weight thereof can be considerably reduced withoutsacrificing necessary strength to resist internal pressures, althoughthese relatively light sheet metal casings are not capable of resistingexternal pressures sufiiciently to adapt them to bear the weight of thegenerator and associated parts.

It has heretofore been proposed in order to relieve the sheet metalcasings of excessive external pressures, to provide a series of strutsor columns extending from the generator downwardly through the inletcasing to the foundation, in order to support the weight of thegenerator directly from the foundation. Such proposed structure whileaccomplishing its object, is objectionable in that the columns provideundesirable obstructions in the inlet passage leading to the turbine andalso because the columns penetrate the sheet metal of the casing,thereby weakening the same. The struts or columns of this prior devicemust also be made of considerable strength and consequently ofrelatively large cross-section, due to their segregation from each otherand to the enormous weight which they must support.

The present invention contemplates elimination of the undesirablefeatures of these prior structures but permits the use of the highlydesirable and efficient sheet metal casing, without undesirablyincreasing the cost of construction and of transportation. These resultsare accomplished by providin a continuous metal ring which is connecteddirectly with the turbine speed ring and has a flange extendinglaterally over the in let casing, upon which the generator and theassociated elements are supported. By making this supporting ringcontinuous and of frusto-conical shape, the same may-be madecomparatively light in structure in order to provide the necessarystrength. The supporting ring is, moreover, constructed of relativelyshort vertical height in order to reduce to a minimum the weight thereofand hence the cost of transportation. In order to provide a pit ofsufiicient or necessary height between the turbine and the generator, anannular wall of concrete is provided between the generator and thesupporting ring. ,This concrete wall can be constructed at relativelylow cost from materials obtainable at the place of installation.

A clear conception of an embodiment of the invention may be had byreferring to the drawing accompanying and forming a part of thisspecification in which the various parts are referred to by suit-ablereference characters.

The single figure of the drawing represents a transverse verticalsection through a direct-co1mected hydraulic turbine installation of thevertical shaft type.

The reaction turbine runner 1 is direct connected to the lower extremityof a vertical main shaft 2 to the upper extremity of which the rotor ofa dynamo-electric machine. 3 is also direct-connected. The turbinerunner 1 is housed within a suitable turbine casing 15 having a mainshaft hearing associated therewith. The turbine cas ing 15 is supportedupon the main foundation 12 and has a cast metal speed ring 5 associatedtherewith adjacent the periphery of the runner 1. The speed ring 5 is ofusual construction having-stationary guide vanes 6 and being alsosupported directly upon the foundation 12. Between the stationary guidevanes 6 of the speed ring and the inlet opening to the runner are located a series of adjustable guide vanes 1 which are manipulable bymeans of guide vane actuating mechanism of usual construction, notshown, associated with the upper extremities of the guide vane stems.

The sheet metal spiral casing 7 forms a fluid conducting conduit 13 forconducting water from the penstock to the speed ring. The discharge endof the turbine runner 1 communicates with the tail race through theusual draft tube 8.

Between the dynamo-electric machine 3 and the hydraulic turbine is aturbine pit 9 access to which is effected through a passage 11.Surrounding the lower extremity of this pit is a rigid supporting ring10 comprising a frusto-conical downwardly converging wall 18 and anoutwardly project ing horizontal flange 16 having bracing ribs 19 andformed integral with the upper extremity of the wall 18. The ring 10 iscomparatively light in structure but is of suflicient rigidity andstrength to provide a stable support for a relatively great weightresting upon the flange 16. The lower extremity of the wall 18 restsdirectly upon and is secured to the top of the speed ring 5. The upperflange 16 extends laterally relatively to the direction of flow offluid, over the relatively light yield-able casing 7 which is preferablyformed of sheet metal or similar yieldable material. The casing 7 is ofsuch form that it will readily resist enormous internal pressures butwill not safely withstand excessive external loading such as the weightof a generator Without yielding and possibly collapsing. Surrounding thepit 9 and located directly above and in vertical alinement with theflange 16 of the ring 10, is a preferably annular concrete wall or pier11 which spans the gap between the dynamo electric machine 3 and thesupporting ring 10. The flange 16 of the ring 10 is preferably providedwith a number of relatively small openings 20 for facilitating union ofthe concrete wall 11 with the concrete foundation 12. The structure ishowever such that substantially the entire weight of the wall 11 and ofthe superposed elements is carried by the ring 10 and speed ring 5.

It will be noted that the generator 3 is of such diameter that itprojects a considerable distance over the body of the spiral casing 7.This is ordinarily the case in in stallations of this kind operating atrelatively low speed. By providing the supporting ring 10 which issupported from the foundation 12 through the speed ring 5, forming thisring so as to extend outwardly over the casing 7 to points directlybelow the outer portion of the generator 3, and inserting the concretevertical wall 11 between the generator 3 and the ring 10, a rigidsupport is provided between the generator 3 and the foundation 12without in any manner interfering with sheet metal casing 7. The onlyexternal pressure which this casing 7 is required to withstand is thenegligible pressure due to the weight of the concrete embedding thesame, substantially the entire weight of the generator 3, and concretewall 11 and the pit ring 10 being borne by the foundation 12 through thespeed ring 5. By avoiding extension of the supporting ring 10 from thespeed ring 5 to the lower surface of the generator and along the entirelength of the pit 9, the weight of this ring may be reduced to a minimumthereby minimizing the cost of construction and of transportationthereof. By forming the ring 10 continuous and of outwardly flaringshape, the weight thereof may be reduced to a minimum thus furtherreducing the cost of construction and of transportation.

While the invention has been disclosed as applied specifically to avertical shaft turbins of the Francis type, it will be noted that thesame is applicable to other types of hydraulic machines. It should beunderstood that it is not desired to limit the invention to the exactdetails of construction herein shown and described for variousmodifications may occur to a person skilled in the art.

It is claimed and desired to secure by Letters Patent:

1. In a hydrauli machine, a fluid conducting casin a foundation, meanscarried by .7 said foundation and extending laterally over said casing,a dynamo electric machine above said casing, and an intermediate support between said machine and said means.

2. In a hydraulic machine, a fluid conducting casing, a speed ringassociated with said casing, a foundation upon which said speed ring issupported, means carried by said speed ring and extending laterally oversaid casing, a dynamo-electric machine above said casing, and anintermediate support between said machine and said means.

3. In a hydraulic machine, a sheet metal casing, a speed ring associatedwith said casing, a foundation supporting said ring, a turbine runneradapted to receive fluid from said casing through said speed ring, adynamo-electric machine connected to said runner and located above saidcasing, and a plurality of supports arranged in series between saidmachine and said ring.

4. In a hydraulic machine, a fluid conducting casing, a foundation, aspeed ring supported by said foundation and associated with said casing,a continuous ring carried by said speed ring and extending laterallyover said casing, a dynamo-electric machine above said casing, and anintermediate support between said machine and said continuous ring.

5. In a hydraulic machine, a sheet metal casing, a foundation, a speedring sup orted by said foundatlon and associated wit said casing, acontinuous metal ring supported by said speed ring and extendin oversaid casing, a dynamo electric mac ine above said casing, and a concretewall between said machine and said continuous ring.

6. In a hydraulic machine, a fluid conducting casing, a foundation,means carried by said foundation and extending laterally over saidcasing, mechanism located above said casing, and an intermediate supportbetween said mechanism and said means.

7 In a hydraulic machine, an annular fluid conducting casing, afoundation, a speed ring associated with said casing and supported uponsaid foundation, means carried by said speed ring and extendinglaterally over said casing, mechanism located above said casing, and anintermediate sup port between said mechanism and said means.

8. In a hydraulic machine, a yieldable fluid conducting casing, afoundation, rigid means carried by said foundation and ex tendinlaterally over said casing, mechanism a ove said casing, and anintermediate support between said mechanism and said rigid means.

9. In a hydraulic machine, a yieldable fluid conducting casing, afoundation, a rigid speed ring associated with said casin and supportedby said foundation, a rigi member carried by said speed ring and extending laterally over said casing, mechanism located above said casing,and a concrete wall between said mechanism and said member.

10. In a hydraulic machine, a fluid con- I ducting casing, a foundation,means carried by said foundation and affording a base of substantialwidth extending over said casing, mechanism located above said base, andan intermediate support between said mechanism and said base.

11. In a hydraulic machine, a yieldable fluid conducting casing, afoundation, rigid means carried by said foundation and affording a baseof substantial width extending over said casing, mechanism above saidcasing, and an intermediate support between said mechanism and saidbase.

12. In a hydraulic machine, a yieldable spiral fluid conductin casing, afoundation, a speed ring associate with said casing and supported bysaid foundation, a rigid element associated with said ring and affordinga base of substantial width extending over said casing, an energyabsorbing device located above said base, and a concrete wall betweensaid device and said base.

In testimon whereof the signature of the inventor is a xed hereto.

ARNOLD PFAU.

Copies of this patent may be obtained for five cents each, by addressingthe "Commissioner of Patents, Washington, D. 0.

